Attachment plug cap



June 21, 1932.

ATTACHMENT PLUG CAP Filed March 28, 1929 H. HUBBELL, JR 1,864,353

Patented June 21, 1932 UNITED stares HARVEY HUBBELL, J'B., F BRIDGEPORT,CONNECTICUT ATTACHMENT PLUG CA1 Application filed March 28,1929. SerialNo. 350,655.

This invention relates to an attachment plug cap such as are used forplugging into a receptacle for the distribution of electric current tovarious electric apparatus or attachments, and has for an object toprovide a cap by means of which more than one such device may beconnected to receive current from a single rece tacle.

It is also an o jectof the invention to provide such a device which maybe wired so that if two attachments are plugged in at the same time theymay be operated either in series or in parallel.

It is a further object of the invention to provide a construction whichmay be wired so that the cap may be used as an ordinary cap.

lVith the foregoing and other objects in view, the invention consists incertain novel features of construction, combinations and arrangements ofparts as will be' more fully disclosed in connection with theaccompanyingdrawing. In this dlEIWlIlQ',

Fig. 1 is a longitudinal section through the device but showing thereceptacle and blade contacts in elevation. This figure also includes astandard attachment plug cap shown in side elevation with a portion ofthe body broken away to indicate the manner of connecting the leadwires. This figure indicates a wiring for the device that when used witha standard cap the two attachments served are in series.

Fig. 2 is a top plan view of my improved cap.

Fig. 3 is a bottom plan view thereof.

Fig. 4 is a side elevation of the device showing in dottedlines astandard cap plugged into the same.

Fig. 5 is a diagrammatical view showing an optional way of wiring thedevice so that it may be used as an ordinary cap.

Fig. 6 is another diagrammatical view showing another optional way ofwirmg the device for use with the standard cap so that the twoattachments will be in parallel.

This improved cap and plug comprises a body member 10 of insulatingmaterial having chambers or recessesdl opening from one end thereof toreceive receptacle contacts 12 and 13 of the usual flat spring metalcontudinal passages passing through the b0 y.

At its inner end the body is somewhat recessed, as shown at 16, toenclose between its outer walls the binding post screws and the meansfor mounting the contacts in the body. Molded into the body is an eyelet17 projecting from the bottom wall of shoulder 18 of the recessed end ofthe body, and thecontact 12 has a lateral foot 19 resting on this wallwith an opening to receive the eyelet. A contact blade 20 projects fromthe end of the body and has a perforated lateral foot 21 receiving saideyelet and resting on top of the foot 19 of the contact 12. The twocontacts 12 and 20 are secured to the body by rolling over the end 23 ofthe eyelet and at the same time the two contacts are in electricalengagement. The eyelet is threaded for the usual type of binding postscrew 24 for attachment of a lead wire. Another contact blade 25 spacedat proper distance from the blade 20 is mounted on the end of the bodyby a similar eyelet 26 molded in the body and carrying a binding postscrew 27. The two contacts 20 and 25 may be made of different widths toprovide a polarized cap. The end wall 18 of the cap is also providedwith a deeper recess 28 on the bottom wall of which is mounted contact13, it being secured to the body by means of a base plate 29 mounted onthis shoulder by an eyelet 3O molded into the body, the contact 13 beingsecured to this base plate 29 by any suitable means, such as a rivet 31.The eyelet 30 carries a binding post screw 32 for connection of a leadwire. In the construction so far described the contacts 12 and 20 areelectrically connected while the contactsl3 and 25 are'insulate'd fromeach other and from the other contacts.

The body member 10 also has a longitudinal ing connected to the bladepassage 33 for lead wires for attachment to the various contacts, andthis passage opens through the side of the body, as shown at 34, so asnot to interfere with the used a standard attachment plug cap 35 withthis plug cap. The passage 33 also opens through the outer end 36 of thebody member and it is preferred that the opening 34 communicate withthis opening in the end of the body so that the leads 37 -38 may leadthrough either the end or the side wall of the body withoutdisconnecting them from the binding post screws. This device is really acombination cap and receptacle and when in use the blades 20 and 25 areplugged into any standard receptacle to secure current therefrom andanother similar cap or a standard cap 35 may be plugged into-the deviceby inserting its contact blades, such as blades 39 and 40, into theopenings 14 and 15 to, engage the receptacle contacts 12 and 13. Withthe construction and arrangement shown the device may be wired so thatthe two attachments supplied respectively by my improved cap and the capplugged into it are connected in series or parallel, or it may be wiredso that my improved device may be used as an ordinary cap for supplyingcurrent to a single attachment. Referring to Fig. 1 it will be seen thatthe lead wires 37 and 38 from the electrical attachment to be operated,indicated by the circle 41, are connected to binding screws 27 and 32and are, therefore, connected to the contacts 25 and 13. Now if thisplug cap is plugged into a receptacle the blades 20 and 25 will en gagethe contacts in the receptacle. Then if the blades 39 and 40 of astandard cap 35 are inserted in the openings 14 and 15 to engage thecontacts 12 and 13 the attachment, indicated by the circle 42, fed bythis cap will be in series with the attachment 41 fed by the first cap,the leads 43 and 44 from the attachment 42 becontacts 39 and40 by thebinding post screws 45 and 46. This is because if we consider thecurrent enters through the blade 25 it passes by lead 37 to attachment41 and then by lead 38 to contact 13 from which it passes by contact 40and lead 44 to attachment 42,- returning through the lead 43, contact39, contact 12 and back to I the outlet receptacle through the contact20.

If it is desired to use my improved device as an ordinary attachmentplug cap, all that is necessary is to connect the lead wires 37 and 38from the attachment in Fig. 5. That is, the lead 37 is connected to thebinding screw 27 and thus the blade contact 25, while the lead 38 isconnected to the binding screw 24 and thus the contact 20. If this plugis now plugged into a receptacle the attachment 41 would be suppliedwith current in the usual manner.

In Fig. 6 is shown a wiring in which both attachments 41 and 42 areoperated in paral- 41, as indicated lel. In this arrangement lead 38 isconnected to binding screw 24 and blade contact 20, and lead 37 isconnected to binding screw 27 and blade contact 25. Then there is atie-over 47,

From the foregoing escription it will seen that I have provided a simpleand effective construction and arrangement which without changing theconstruction may be wired so that when used with a standard attachmentplug cap two electrical attachments may be operated either in series orparallel as is found desirable, or the device may be used as a standardcap if such a cap is not available.

Having thus set forth the nature of my invention, what I claim is:

In an attachment plug cap, an'insulating body member having a pair oflongitudinal passages opening through the opposite ends thereof andproviding openings 1n one end of the body for entrance of contactblades, receptacle contacts projecting into said passages from the otherend, a pair of blade contacts projecting from the latter end of thebody, one of the blade contacts being permanently electrically connectedto one of the receptacle contacts, means for connecting a lead wire tosaid combined blade and receptacle contacts, the other blade contactbeing separate from the other receptacle contact, means for connecting alead wire to said other blade contact, and means for connecting a leadwire to said other receptacle contact, whereby circuits may be connectedeither in series or in parallel through said plug.

In testimony whereof I aflix my signature.

- HARVEY HUBBELL, JR.

